The field of the invention is automatic animal identification systems, and more particularly, systems for electronically identifying dairy cows and the like.
To optimize milk yield in dairy cows, automated computer systems are being utilized to collect data on each animal and to automatically dispense feed to it. The amounts of feed dispensed to a particular cow depend on its age, its health and its stage in the lactation cycle, and hence, it is necessary to identify each animal. Numerous devices are known for enabling the visual identification of dairy cows, including ear tags, neck bands and chains, tail bands and blank markers. However, such visual identification of animals requires the manual entry into the computer system of the proper identifying code which is both expensive and subject to error.
Automatic animal identification systems have been proposed. These include a passive transponder which is attached to, or implanted in, the animal. This transponder is triggered when the animal passes through an archway of energized coils. When thus triggered, the transponder transmits a unique code to a receiver which identifies the animal. On a dairy farm, for example, the archway is disposed in a passageway leading to the milking parlor so that the animal is identified just prior to feeding. The difficulty with such prior automated systems is their high cost, size and susceptibility to noise and other severe environmental conditions.